Coupling



Nov. 10, 1953 w. J. SPENGLER COUPLING Filed Sept. 21. 1949 1 FIG.2. FIG.3.

FIG.

INVENTOR Dale. a. 64.1.4110

ATTORNEY Patented Nov. 10, 1953 ITED OFFICE COUPLING WalteneLLSnenglcr;:SidneygN. .Y.', yasslg'norsto BcndixAviationzflocporation; New 102k; Y.) ascotponticmnfltnalaware Application-September 21, 19!9;"S'erla'l No. 116.924

LClaimsl. (01. 64-25) This-inventionrelatestocouplingsior-urotatablei parts and: more particularly to couplingszawhich permit limited relative rotation: of: said :parts An: object of the present invention is to -pro vide a novel speed responsive-device fondrivably coupling two rotatable parts.

Another object of the inventioniszto provide a: novel coupling of the-' centrifugally-responsive type for connecting and varying the 'angular relationship of a pair of rotati-ng members.

A further object is to provide a device of the abovecharacter which is of small size-and weight and which is well adapted for usein automatically controlling-the timing of the sparks'in the ignition system of anengine.-

Stillanother object is toprovideas'haft-I'coupli'ng of the abovetype'which 'embodies xonly'a' small number of'simply constructed parts. which may bereadily and easily assembled to function" in a novel manner and in a relativelysmall space to adjust the relative angular positions of th'e parts connected thereby.

A still further object isto-provideanovelzcou pling which will-effect a plurality of variationsin: the angular relation of V the 1 connected: parts: at" different predetermined speeds of rotation as" the:

speed of rotationincreases.-

Another object" is to provide a device of'the above character which; is"novelly=.constructed in;-

30 centrifugal weights-and increase the bearing sur+ face therefor without adversely aflecting the such amanner as to reduce the length of :the

availableiorce for effecting thedesired-result:lt

tion of rotation.

The above and further objects "and: novel tea-@- tures of the inventionwill* more-. fully appear from the following detailed descriptionwhenzth'e same is read in connection with th'eaccompanylng:

It is to be expressly understoodyhowdrawings.

for the purpose: of

ever; that the drawings 'are illustration only and are not intendedfi'torrdefine the limits of the invention; reference -for thisz latter purpose being had-primarilytmthe apipended claims. I

In the drawings, wherein like reference char.-

acters refer to like parts throughout the several views,

Fig. 1 is an end' elevation view,"looklng toward: theright in Fig. 2, of one formof 'couplin'grcom-lprehended by the invention;

Fig: a secti'onal side elevation: view of "said device; the section being taken substantially online 2 -2fof F1'g.' 1;

Fig.3 is a detail view, with parts broken away if andusectioned, of one set of fiyweights, the view being taken on line 3!3 of Fig. 4; and

Fig. 4-is an exploded' view of the device of Fig;

2, partly in section and with parts broken away;

and lwith the nearest'set of flyweights removed.

A-single embodiment of the-invention is illus-- trated in: the drawings, byway of example,-in a form adapted for use in controlling the angular:

relationship of two rotating partssuch-as a-circult breaker cam or distributor finger of an engine ignition 'system and the drive shaft therefor.

In such a construction; the'coupling shown" is effective to automatically advance and retard the occurrence of theigniticn spark in relation-to the position of the 'enginepistons in the cylinders and in response to-the speed of the engine. Although thedevice may be-d-riven'fr'om either end;

for the purpose or simplifying the description the.

left hand member; as viewedin Figs; 2 "and 4, willbe: considered to b'e the driving member.

In, the A form: shown the simplified coupling comprises a drivlng member or assembly- It, oneor-a pair-of *fiyweight'asscmblies II and a driven member-or assembly I2; The driving assembly includes a tubular hub ld which is provided with a keyway- I5 by means of which the same may be drivably connected-to a-power shaft (not shown). Extending-radially from hub I4 is a flange that may b'e in theic'rm of a -disk I6; The hub and disk maybe'integralaor otherwise suitably se-- cured together.

A' pair of diametrically disposed stub shafts orbearingpins I1, I8 are secured to and protect-axially from flange I6 near'the-periph'ery-th'ereof. The driven 'assemblyis similarly constructed and comprises'tubular'hub' I9; flangeor disk ZI, and pivot pins or stub shaft's'22, 23F

The latterand pins I 1; I8 maybe secured in place by forming over "and-riveting the ends thereof against di'sks; 2i and I6, respectively; but any other suitable know-n means of fastening-the samemay be employedt When'thedriving and driven" members areassembled-with each other, hub I9' has a" sliding fit- 'on hub-"I 4- (Fig: 2) so that said" members nlay :move angularly relative to each other;

Intheinterest of better mechanical balance tWocentrlfugal flyweight assemblies are provided although only one is essential.

will be now described in detail. I I zcompvisestwo wei-ghts 2i;- ZS WhichLmaybe-of Since both these assemblies are oflde'ntical "construction only one. Each assembly identical construction to thereby minimize the number of different parts and hence benefit from the several known advantages accruing from such duplication of parts. The reduced ends 26, 26 of the weights overlap and are drilled to receive a pivot pin 2'! whereby the same are pivotally connected together. This connection is very beneficial in preventing bending of the weights and vibration thereof during operation of the coupling. The other or large ends of the weights are also transversely boredone for receiving a supporting pin I! on driving assembly I and one for receiving a pin 22 on driven assembly 12. It will be noted that the pins l1 and 22 provide long bearing surfaces for the weights and hence prevent lateral vibration of the latter. The second set of centrifugal weights 24 and 25' (partially shown only in Fig. 1) is mounted on driving pin i8 and driven pin 23.

The pivotally connected weights 24, 25 are normally held in the extended position shown in Fig. 3 by resilient means combined therewith in a novel and simplified manner to take fullest advantage of the space available and to provide what may be called a plural step operation of the centrifugal weights during rotation. Said means, as shown, comprises two simple leaf springs 28 and 29 mounted by common means in spaced relation to each other on the inner face of weight 24 adjacent the axis of rotation. Both springs are held in place in the groove 30 in the inner face of said weight by single set screw 3| threaded into a tapped hole in the weight. The anchored ends of the springs are held in spaced relation by shims or Washers 32.

Spring 28, which is shown as being the shorter of the two, extends across the pivotal connection 2! and engages the bottom of the groove 33 in weight 25, exerting a pressure which tends to hold the weights in the relative positions illustrated. As will more fully appear hereafter, this pressure may be of any desired magnitude or the assembly may be such that no pressure is exerted by spring 28 until the connected ends of the weights are caused to move outwardly away from the axis of rotation (to the right in Fig. 3) to thereby cause the remote ends of the weights on pins l1 and 22 to approach each other. Spring 29 also extends across pivot 21 but the free end thereof does not contact weight 25 until the weights have moved a predetermined amount against the pressure of spring 28 in the manner described in the preceding sentence. This movement of the weights is limited by a slot 34 in disk l6 into which an extended portion 35 of pivot pin 21 projects to act as a stop. The pins 21, 35 engage the elongated side walls of slots 34 and the latter are elongated to provide for assembly suitable for either direction of rotation as pointed out hereafter.

It will thus be seen that when the units of Fig. 4 are in assembled relation (Figs. 1 and 2), one end of the flyweight assembly is pivotally connected at pin I! to the driving unit I!) and the other end is similarly connected to the driven unit [2 at pin 22. Accordingly, upon rotation of the driving unit in a clockwise direction as viewed in Fig. 1, a pull will be exerted through linkage 24, 25 upon the driven unit so that said units will rotate together. This pulling action tends to separate, as far as possible, the remote ends of the two weights that are supported on pins I1 and 22 and thereby supplement the action of spring 28.

As the speed of rotation increases, centrifugal force tends to throw the ends of the weights 24 and 25 connected by pin 21 outwardly from the axis of rotation, the same pivoting about pins H and 22. When this force is suflicient to overcome the opposing forces including the resistance of spring 28, the adjacent ends of the weights will move outwardly from the axis thereby decreasing the acute angle between lines joining the center of pivot 21 with the centers of pivots l1 and 22 and. thus causing the latter pivots to move closer together. This effects relative rotation of the driving and driven units and continues until spring 29 engages weight 25 and exerts a sufllcient pressure to arrest the articulating movement of the weights. After a further increase in speed and hence in the effective centrifugal force, the initial pressure of spring 29 will be overcome and further relative angular movement of the driving and driven units will be effected. The exact nature of the relative movement which is thus effected may be varied by the selection of springs having desired characteristics. When the speed decreases the reverse action will take place. With the parts assembled in the manner described, the driven unit 12 will be caused to advance in relation to driving unit I0 during increases in speed in the direction of the arrow in Fig. 1. If the same results are desired for the opposite rotation, it is only necessary to mount the wei ht 24 on pin I 8 and weight 25 on pin 23. In other words the leading weight (rotation-wise) of each set should be mounted on a pivot pin secured to the driving unit 10 and the trailing weight of each set should be pivotally mounted on the driven unit [2.

I will be understood that springs 28 and 29 may be so calibrated and positioned that predetermined relative movements of assemblies l0 and I 2 may be effected during predetermined ranges of speeds of rotation. Although the springs may be so constructed as to permit gradual changes in the angular relation of said units in accordance with changes of speed, it ma be preferable in some installations that the springs be such as to permit relatively abrupt or sudden changes of predetermined angular extent whenever preselected speeds are attained.

There is thus provided a highly efficient and effective coupling for connecting rotating parts in r such manner as to automatically effect relative angular movement of said parts in accordance with the speed of rotation. The novel construction provided results in a device which is mechanically simple and yet rugged and small in comparison to devices heretofore provided for the same purpose. The total number of parts required is small and the number of different kinds of parts is considerably smaller than the total, thereby greatly reducing the manufacturing cost and facilitating assembly. The space requirements of the present device are less than other comparable devices and in operation it is substantially free of vibration and chattering, thereby enhancing its dependability and accuracy.

Although only a single embodiment of the invention has been illustrated in the accompanying drawing and described in the foregoing specification, it is to be expressly understood that the same is not limited thereto. For example, more or less than two sets of centrifugal weights may be employed and more or less than two springs may be used on each set of weights. Various other changes may be made in the design and arrangement of parts illustrated without departing from the spirit and scope of the invention as will now be understood by those skilled in the art. For a definition of the limits of the invention reference is had primarily to the appended claims.

What is claimed is:

1. In apparatus of the class described, a driving member, a driven member free for angular movement relative to said driving member, coupling means for drivably connecting said members comprising a pair of centrifugally actuatable weights, means pivotally connecting one of said weights adjacent one end thereof to said driving member, means pivotally connecting the other of said weights adjacent one end thereof to said driven member and means pivotally connecting the other ends of said weights to each other, the axes of said pivotal connecting means being substantially parallel to the axis of rotation of said driving member, and resilient means for resisting pivotal movement of said weights in one direction about the pivotal connecting means therefor, said resilient means comprising at least two leaf spring means having corresponding ends thereof secured to said one weight, said secured ends being spaced from each other in the direction of said axis of rotation from said one weight, the unsecured portions of said spring means extending from said secured ends in substantially parallel relation to each other, and said spring means being of different lengths with the longer spring means spaced further than the shorter spring means from the weights toward said axis of rotation, the free end of the shorter spring means being normally in sliding engagement with a surface of said other weight and the free end of the longer spring means being normally spaced from said other weight but adapted to engage said surface of the latter at a place beyond the end of the shorter spring means when the weights have been moved a predetermined amount by centrifugal force, said surface of said other weight being one which faces toward said axis of rotation and each said spring means being unconfined and free to flex throughout the length of said unsecured portion thereof.

2. In apparatus of the class described, a driving member, a driven member free for angular movement relative to said driving member, and coupling means for drivably connecting said members comprising a set of pivotally connected centrifugal weights pivotally connected to said members, whereby articulation of said weights effects relative angular movement of said members, means secured to one of said weights and engageable .with the other of said weights for yieldably resisting articulation of said weights in response to centrifugal force, and stop means for limiting articulation of said weights comprising means pivotally connecting the weights and engageable with one of said members.

3. In apparatus of the class described, a driving member, a driven member free for angular movement relative to said driving member, coupling means for drivably connecting said members comprising a pair of centrifugally actuatable weights, means pivotally connecting one of said weights adjacent one end thereof to said driving member, means pivotally connecting the other of said weights adjacent one end thereof to said driven member, means pivotally connecting the other ends of said weights to each other, the axes of said pivotal connecting means being substantially parallel to the axis of rotation of said driving member, and resilient means for resisting pivotal movement of said weights in one direction about the pivotal connecting means therefor, said resilient means comprising a leaf spring rigidly secured at one end to one of said weights and having the other end portion thereof in sliding engagement with the other of said weights to yieldably resist movement of said weights in response to centrifugal force, and stop means for limiting articulation of said weights, said stop means including an extension on the means pivotally connecting the ends of said weights to each other engageable with one of said members.

4. In apparatus of the class described, driving means, driven means, and means operatively connecting said driving and driven means comprising weight means pivotally connected to said driving means, weight means pivotally connected to said driven means, means pivotally connecting said weight means to each other, the axes of said pivotal connections being substantially parallel to the axis of rotation of said driving and driven means, resilient leaf spring means rigidly secured at one end thereof to one of said weight means and having the free end thereof in sliding contact with the other said weight means for resisting movement of both said weight means in response to centrifugal force during rotation of said driving and driven means, said resilient means being between said axis of rotation and said weight means and unconfined and free to flex throughout that portion of its length from the point of attachment on said one weight means to said free end thereof in response to movement of said weight means by centrifugal force, and the surface on said weight means engaged by said free end being a surface facing said axis of rotation, and means for limiting the movement of said weight means in response to centrifugal force.

WALTER J. SPENGLER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,273,095 Rilling July 16, 1918 1,590,772 Moore June 29, 1926 1,967,445 Mallory July 24, 1934 FOREIGN PATENTS Number Country Date 285,992 Great Britain 1928 604,746 France 1926 

